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Issue: Vol. 609 No. 1: 17 Aug. 2023
Type: Article
Published: 2023-08-17
DOI: 10.11646/phytotaxa.609.1.1
Page range: 1-9
Abstract views: 244
PDF downloaded: 192

Petalidium karasbergense (Acanthaceae), a new species from Namibia

Independent Researcher; P.O. Box 21168; Windhoek; Namibia; H.G.W.J. Schweickerdt Herbarium; Department of Plant and Soil Sciences; University of Pretoria; Pretoria; 0002 South Africa
H.G.W.J. Schweickerdt Herbarium; Department of Plant and Soil Sciences; University of Pretoria; Pretoria; 0002 South Africa; South African National Biodiversity Institute; Private Bag X101; Pretoria; 0001 South Africa
Eudicots desert endemism flora Great Karas Mountains Groot Karasberge Petalidium lucens Petalidium parvifolium Ruellieae taxonomy

Abstract

Petalidium karasbergense, here described as a new species, is only known from the Groot Karasberge (Great Karas Mountains) in southeastern Namibia where it grows on arid hillsides in dwarf shrubland. Diagnostic morphological characters for P. karasbergense include the rigid, tapering and often spinescent distal stems and lateral branchlets, grey, grey-white or grey-black bark (white to cream when young), strigulose, glabrescent vegetative parts, oblanceolate to narrowly obovate leaves, and the free to almost free bracteole pairs (not connate at the base). A comparison of some of the more prominent features to differentiate Petalidium karasbergense from P. parvifolium, its morphologically most similar relative, and P. lucens with which its distribution range marginally overlaps, is provided. Based on IUCN Red List categories and criteria, a conservation assessment of Vulnerable VU D1 is recommended for the new species.

 

References

  1. Beentje, H. (2016) The Kew plant glossary: an illustrated dictionary of plant terms, 2nd ed. Kew Publishing, Kew, 184 pp.
  2. Edwards, D. & Leistner, O.A. (1971) A degree reference system for citing biological records in southern Africa. Mitteilungen der Botanischen Staatssammlung München 10: 501–509. [https://biostor.org/reference/185348]
  3. Figueiredo, E. & Smith, G.F. (2008) Plants of Angola/Plantas de Angola. Strelitzia 22. South African National Biodiversity Institute, Pretoria, pp. 1–279. [https://www.sanbi.org/documents/plants-of-angola-strelitzia-22/]
  4. Germishuizen, G. & Meyer, N.L. (Eds.) (2003) Plants of southern Africa: an annotated checklist. Strelitzia 14. National Botanical Institute, Pretoria, 1231 pp.
  5. IUCN (2012) IUCN red list categories and criteria: Version 3.1, 2nd edn. IUCN Species Survival Commission, Gland, Switzerland and Cambridge U.K., iv + 32 pp.
  6. Manktelow, M. (2000) The filament curtain: a structure important to systematics and pollination biology in the Acanthaceae. Botanical Journal of the Linnean Society 133 (2): 129–160. https://doi.org/10.1111/j.1095-8339.2000.tb01539.x
  7. Mendelsohn, J., Jarvis, A., Roberts, C. & Robertson, T. (2002) Atlas of Namibia. Philip, Cape Town, 200 pp.
  8. Meyer, P.G. (1961) Beiträge zur Kenntnis der Acanthaceen Südwestafricas (III). Mitteilungen der Botanischen Staatssammlung München 4: 59–72. [https://biostor.org/reference/185199]
  9. Meyer, P.G. (1968) Acanthaceae. Prodromus einer Flora von Südwestafrica 130: 1–65.
  10. Nees von Esenbeck, C.G. (1832) Acanthaceae India Orientalis. In: Wallich, N. (Ed.) Plantae Asiaticae rariores: or descriptions and figures of a select number of unpublished East Indian plants, vol. 3. Treuttel & Würtz, London, pp. 70–117. https://doi.org/10.5962/bhl.title.468
  11. Obermeijer, A.A. (1936) The South African species of Petalidium. Annals of the Transvaal Museum 18: 151–162.
  12. Schinz, H. (1926) Acanthaceae. Vierteljahrsschrift der Naturforschenden Gesellschaft in Zürich 71: 145–146.
  13. Swanepoel, W. (2020) Petalidium kaokoense (Acanthaceae), a new species from Namibia. Phytotaxa 468 (3): 236–242. https://doi.org/10.11646/phytotaxa.468.3.1
  14. Swanepoel, W. & Manzitto-Tripp, E. (2022) Petalidium sesfonteinense (Acanthaceae), a new species from the Kaokoveld, Namibia. Phytotaxa 549 (8): 127–135. https://doi.org/10.11646/phytotaxa.549.2.1
  15. Swanepoel, W., Nanyeni, L. & Van Wyk, A.E. (2022) Petalidium mannheimerae (Acanthaceae), a new species from Namibia and South Africa, with notes on the taxonomic identity of P. parvifolium. Phytotaxa 561 (1): 1–13. https://doi.org/10.11646/phytotaxa.561.1.1
  16. Swanepoel, W. & Van Wyk, A.E. (2023) Petalidium konkiepense (Acanthaceae), a new species from Namibia. Phytotaxa 585 (1): 29–38. https://doi.org/10.11646/phytotaxa.585.1.3
  17. Thiers, B. (2019) Index Herbariorum: A global directory of public herbaria and associated staff. New York Botanical Garden’s Virtual Herbarium. Available from http://sweetgum.nybg.org/ih/ (accessed October 2022)
  18. Tripp, E.A., Tsai, Y.E., Zhuang, Y. & Dexter, K.G. (2017) RADseq dataset with 90% missing data fully resolves recent radiation of Petalidium (Acanthaceae) in the ultra-arid deserts of Namibia. Ecology and Evolution 7 (19): 1–17. https://doi.org/10.1002/ece3.3274
  19. Van Wyk, A.E. & Smith, G.F. (2001) Regions of floristic endemism in southern Africa: a review with emphasis on succulents. Umdaus Press, Hatfield, Pretoria, 199 pp.